From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date: Fri, 23 Feb 2018 18:29:02 +0000 (+0000)
Subject: arm64: mm: don't write garbage into TTBR1_EL1 register
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=35d75b7bfc67520fb1d93b63ab3ae27992006f66;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

arm64: mm: don't write garbage into TTBR1_EL1 register

Stable backport commit 173358a49173 ("arm64: kpti: Add ->enable callback
to remap swapper using nG mappings") of upstream commit f992b4dfd58b did
not survive the backporting process unscathed, and ends up writing garbage
into the TTBR1_EL1 register, rather than pointing it to the zero page to
disable translations. Fix that.

Cc: <stable@vger.kernel.org> #v4.14
Reported-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 329a1c43365e..139320a7f7a2 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -155,7 +155,7 @@ ENDPROC(cpu_do_switch_mm)
 
 .macro	__idmap_cpu_set_reserved_ttbr1, tmp1, tmp2
 	adrp	\tmp1, empty_zero_page
-	msr	ttbr1_el1, \tmp2
+	msr	ttbr1_el1, \tmp1
 	isb
 	tlbi	vmalle1
 	dsb	nsh